Scientists have mapped 100-year-old brains of two extinct thylacines — better known as the Tasmanian tiger — to reveal how the carnivore was wired to be a predator.

Tasmanian tiger key points

Key points

Researchers image brain of extinct Tasmanian tiger for the first time

Brain architecture indicates thylacine would have been predatory

Imaging techniques could be used on other extinct animals

Sophisticated imaging shows the thylacine had a larger brain than some other Australian carnivores, with more cortex allocated to decision-making and planning behaviours.

Professor Ken Ashwell, an anatomist at the University of New South Wales and co-author of the research, said no-one had ever studied the thylacine brain in such detail before and that the findings opened the door for use on other extinct and endangered animals.

"What's quite exciting about it for comparative neuroscience and brain evolution is that there are many brains sitting in museums of rare animals, extinct animals," he said.

"[This] opens up the possibility of analysing the internal structure of those brains in ways that were never possible before."

The distribution of fibres connecting different parts of the brain in the Tasmanian devil and Tasmanian tiger

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The last Tasmanian tiger, a carnivorous marsupial about the size of a medium-to-large size dog, died in Hobart Zoo in 1936.

Scientific evidence of the natural behaviour of the thylacine is limited, so researchers turned to the well-preserved brains of two thylacines housed in Smithsonian Institution in the US and the Australian Museum to gain an insight into the iconic animal.

Using a technique called diffusion tensor imaging (which looks at how water diffuses inside parts of the brain) alongside traditional magnetic resonance imaging (MRI), the researchers mapped how molecules moved through the brain of the thylacine while it was alive to reveal the neural wiring of different brain regions.

They then compared this to two brains from Tasmanian devils — one of which was a similar age to the thylacine brains, the other from a recently deceased animal — to see what they could infer about the behaviour of each animal from the architecture of its brain.

"When you look at the cerebral cortex of any mammal there's areas to do with decision making and planning, there's areas to do with motor function, there's areas to do with sense of touch, vision," Professor Ashwell said.

"Depending on the relative size of those you can draw conclusions about behavioural repertoire."

The study found thylacines had more of their cortex devoted to "complex cognition" activities associated with being a hunting animal — like planning actions and making decisions.

That accords with observations made of Tasmanian tigers before they became extinct and features of their anatomy.

Meanwhile, the smaller frontal area of the brains of the Tasmanian devils suggested less of their brain is committed to complex decision making — which was broadly in line with what is known about the carnivorous devil as a scavenger.

The research was also consistent with theories of brain evolution that suggest that brains became more modularised as they became larger, wrote the researchers.

Insight into the evolution of mammals and marsupials

Scientific evidence of the behaviour of the thylacine in their natural habitat is limited.